May 1, 2007

The champion phallus from this Meller’s duck is a long, spiraling tentacle. Some ducks grow phalluses as long as their entire body. In the fall, the genitalia will disappear, only to reappear next spring....

Most of the time it remains invisible, curled up inside a bird’s body. During mating, however, it fills with lymphatic fluid and expands into a long, corkscrew shape. The bird’s sperm travels on the outside of the phallus, along a spiral-shaped groove, into the female bird.

Okay, now, why does the NYT have a big story about a post-doc whose research is measuring duck dicks? Score one big point if you guessed that her theory has to do with the superiority of the female:

Species with more forced mating tend to have longer phalluses. That link led some scientists to argue that the duck phallus was the result of males’ competing with one another to fertilize eggs....

Dr. [Patricia] Brennan realized that scientists had made this argument without looking at the female birds.....

Working with Kevin McCracken of the University of Alaska and his colleagues, she caught and dissected 16 species of ducks and geese, comparing the male and female anatomy.

If a male bird had a long phallus, the female tended to have a more elaborate lower oviduct. And if the male had a small phallus, the female tended to have a simple oviduct....

Dr. McCracken... is struck by the fact that it was a woman who discovered the complexity of female birds. “Maybe it’s the male bias we all have,” he said. “It’s just been out there, waiting to be discovered.”

I like the part of the article where she says she hasn't proven any of it yet, all she has is the correlations. In other words, the old theory didn't take into account the correlations, but her hypothesis, which led to discovering the correlations, doesn't necessarily describe accurately the process by which the correlations came to be. So there is probably another theory that explains the correlations that no scientist has thought of yet. Hopefully that theory won't be inspired by bias of any kind.